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适当增加种植密度提高春玉米冠层钾素的吸收运转和对籽粒的贡献率

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植物营养与肥料学报 2024年第2期30卷 307-314页

作者：王昭月蔡颖杜峰屹肖春花石河子大学农学院/绿洲生态农业重点实验室新疆石河子832003

【目的】种植密度与钾素营养是影响春玉米产量和品质的重要因素,探索种植密度与钾素吸收转运的关系,为实现新疆密植玉米高产、高效、优质提供理论基础。【方法】于2015、2016年在新疆伊犁新源县开展大田试验,裂区试验设计,品种为主区,... 详细信息

【目的】种植密度与钾素营养是影响春玉米产量和品质的重要因素,探索种植密度与钾素吸收转运的关系,为实现新疆密植玉米高产、高效、优质提供理论基础。【方法】于2015、2016年在新疆伊犁新源县开展大田试验,裂区试验设计,品种为主区,密度为副区。试验材料为2个具有高产潜力且在当地玉米产区适应性广的杂交品种先玉335和郑单958。设置2个密度水平,分别为大田常规栽培密度(M1,60000株/hm^(2))和高密度(M2,120000株/hm^(2)),于吐丝期和成熟期取样测定春玉米不同器官的干物质量和钾素含量,计算钾素在冠层叶片、茎杆中积累量与转运率,分析其与产量和产量构成因子的相关性。【结果】合理增加种植密度对两个春玉米品种均有显著的增产效果,2015和2016年高种植密度下先玉335籽粒产量分别较常规密度下提高了54.86%、30.97%,郑单958籽粒产量分别提高了36.86%、23.94%。提高种植密度,春玉米冠层叶片、茎秆钾素转运量、转运率和对籽粒的贡献率也随之增加。叶位不同,叶片钾素积累量也不一样,最高钾素积累量在穗位(D7、D8)叶以及穗位下叶片(D9),茎杆钾素积累量从冠层顶部到基部逐渐增加。D7、D8、D9位叶及相应茎节的钾素积累量与产量和有效穗数呈显著正相关,与穗粒数和千粒重呈显著负相关。吐丝期玉米中下部叶片钾积累量与产量显著相关,成熟期与产量显著相关的叶片叶位和茎节上移。【结论】吐丝期春玉米穗位及穗下附近叶片和茎节的钾素积累量对产量的影响较显著。合理增加种植密度能显著提高春玉米群体钾素积累量,有助于春玉米群体冠层叶片和茎杆的钾素吸收、积累与转运,最大限度地激发群体的增产潜力,进而提高春玉米产量。

关键词：春玉米种植密度冠层钾素积累量钾素转运量

基于RBBLA混合模型的文本相似度计算方法

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陕西科技大学学报 2024年第4期42卷 184-190,198页

作者：任喜伟杜丰怡向启怀李兆允赵杉陕西科技大学电子信息与人工智能学院陕西省人工智能联合实验室陕西西安710021 大唐移动通信设备有限公司西安分公司陕西西安710061

文本相似度计算是两个或多个文本之间相似程度的度量,它被广泛用于多个场景.针对现有研究存在的缺乏上下文交互特征捕获、语义结构信息表示不足等问题,提出一种基于RBBLA(RoBERTa-BiLSTM-Attention)混合模型的文本相似度计算方法,该模... 详细信息

文本相似度计算是两个或多个文本之间相似程度的度量,它被广泛用于多个场景.针对现有研究存在的缺乏上下文交互特征捕获、语义结构信息表示不足等问题,提出一种基于RBBLA(RoBERTa-BiLSTM-Attention)混合模型的文本相似度计算方法,该模型基于RoBERTa模型预训练,获得词语的向量化表示,并提取句子中的语义特征;接着使用双向长短期记忆网络及注意力机制提取上下文依赖关系;最后将两句子的文本特征经聚合操作后由Softmax函数处理得到相似度评分结果.将RBBLA模型与RoBERTa等基准模型在LCQMC数据集上进行对比实验,结果表明,与最优模型相比,RBBLA模型在准确率、精确率等指标上分别提升了2.9、2.1个百分点.

关键词：文本相似度 RoBERTa 双向长短期记忆网络(BiLSTM) 注意力机制

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Application of Improved Fuzzy Immune PID Controller to Bending Control System

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Journal of Iron and Steel Research International 2011年第3期18卷 28-33页

作者： REN Xin-yi du feng-shan HUANG Hua-gui ZHANG Shang-bin Institute of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

Based on the hydraulic bending control system,the electrohydraulic servo pressure control simulation model is *** into account of the inadequacy of P-type immune feedback controller,an improved fuzzy immune PID controller is put *** on immune feedback principle of biological immune system,the P-type immune feedback controller is connected with conventional PID controller in series and then in parallel with design fuzzy immune PID *** controller parameters can be adjusted on line by the rules of immune feedback controller and fuzzy *** order to gain the optimal parameters of the controller,the parameters of the controller are off-line optimized by the best multiple optimal model PSO *** simulation results indicate that the method has characteristics of small overshoot,short adjusting time and strong anti-interference ability and *** quality of the strip shape can be further improved.

关键词： electrohydraulic bending system immune feedback control fuzzy control PSO algorithm strip shape

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高校大类分流系统的实现与应用

计算机技术与发展 2024年第1期34卷 171-176页

作者：任喜伟杜丰怡李兆允侯佳蕾陕西科技大学电子信息与人工智能学院陕西西安710021

随着信息化时代的到来,高校教育教学信息化改革已成为不可避免的趋势。为解决传统高校大类分流、专业分班系统中存在的结果不准、效率不高、操作不便等问题,融合手机端、PC端和服务器端,设计并开发了B/S架构下前后端分离的高校大类分流... 详细信息

随着信息化时代的到来,高校教育教学信息化改革已成为不可避免的趋势。为解决传统高校大类分流、专业分班系统中存在的结果不准、效率不高、操作不便等问题,融合手机端、PC端和服务器端,设计并开发了B/S架构下前后端分离的高校大类分流系统。系统采用Vue框架作为前端技术,SpringBoot和MyBatisPlus框架作为后端技术,同时采用MySQL数据库进行数据存储。系统的实现应用了登录验证、前后端分离、信息加密与数据校验等关键技术,以确保安全性和稳定性。分流过程设计了绩点优先和志愿优先两种核心算法,并提供随机分班、“Z字型”折线分班等多种分班算法选择。系统测试以陕西科技大学电子信息与人工智能学院2021级本科生大类分流、专业分班的数据为案例,应用结果表明:该系统人机交互方便实用,能快速获得准确结果,分流分班效率显著提高,有效地解决了传统高校大类分流、专业分班系统存在的问题,为高校教育教学信息化改革提供了有力的支持。

关键词： Vue Springboot MybatisPlus 大类分流专业分班

Exploring charge and spin fluctuations in infinite-layer cuprate SrCuO_(2)from a phonon perspective

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 159-167页

作者： Xin du Pei-Han Sun Ben-Chao Gong Jian-feng Zhang Zhong-yi Lu Kai Liu Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China Department of Physics School of ScienceJiangsu University of Science and TechnologyZhenjiang 212100China Institute of Physics Chinese Academy of SciencesBeijing 100190China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China

The infinite-layer cuprate ACu O_(2)(A=Ca,Sr,Ba)possesses the simplest crystal structure among numerous cuprate superconductors and can serve as a prototypical system to explore the unconventional *** on the first-principles electronic structure calculations,we have studied the electronic and magnetic properties of the infinite-layer cuprate SrCuO_(2)from a phonon *** find that interesting fluctuations of charges,electrical dipoles,and local magnetic moments can be induced by the atomic displacements of phonon modes in SrCuO_(2)upon the hole *** all optical phonon modes of SrCuO_(2)in the antiferromagnetic Néel state,only the A_(1g)mode that involves the full-breathing O vibrations along the Cu-O bonds can cause significant fluctuations of local magnetic moments on O atoms and dramatic charge redistributions between Cu and O ***,due to the atomic displacements of the A_(1g)mode,both the charge fluctuations on Cu and the electrical dipoles on O show a dome-like evolution with increasing hole doping,quite similar to the experimentally observed behavior of the superconducting T_(c);in comparison,the fluctuations of local magnetic moments on O display a monotonic enhancement along with the hole *** analyses indicate that around the optimal doping,there exists a large softening in the frequency of the A_(1g)phonon mode and a van Hove singularity in the electronic structure close to the Fermi level,suggesting potential electron-phonon *** work reveals the important role of the full-breathing O phonon mode playing in the infinite-layer SrCuO_(2),which may provide new insights in understanding the cuprate superconductivity.

关键词： first-principles calculations cuprate superconductors phonon charge and spin fluctuations

Adenylate cyclase activates the cAMP signalling pathway to enhance platelet-rich plasma-treated Achilles tendon disease,a theoretical bioinformatics-based study

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World Journal of Orthopedics 2024年第2期15卷 192-200页

作者： Jing-yi Sun Cai Li feng-ying du College of Basic Medical Science Qilu Medical UniversityZibo 255300Shandong ProvinceChina Department of Gastroenterological Surgery Shandong Provincial Hospital of Shandong First Medical UniversityJinan 250021Shandong ProvinceChina

The effectiveness of platelet-rich plasma(PRP)for the treatment of Achilles tendon disorders still needs to be evaluated through a series of prospective studies,but genomic analysis can reveal the existence of complementary PRP treatment *** on the 96 platelet activation-related genes in the Kyoto Encyclopedia of Genes and Genomes(KEGG)database,we performed Gene Ontology functional enrichment analysis and KEGG enrichment analysis,pathway correlation analysis,and enrichment mapping to determine the enrichment results of the gene set enrichment analysis and found that the cAMP signalling pathway may be the key to enhancing the effectiveness of PRP *** cAMP signalling pathway interacts with the Rap1 signalling pathway and cGMPPKG signalling pathway to mediate the entire pathophy-siological process of Achilles tendon ***,ADCY1-9 may be the key to the activation of the cAMP signalling *** based on the data in the Gene Expression Omnibus database,it was found that ADCY4 and ADCY7 may be the players that play a major role,associated with the STAT4-ADCY4-LAMA5 axis and the GRbeta-ADCY7-SEMA3C axis,which is expected to be a complementary target for enhancing the efficacy of PRP in the treatment of Achilles tendon disease.

关键词： Platelet-rich plasma Achilles tendon disease cAMP Adenylate cyclase Complementary target

Asymmetric Partial Hydrosilylation of 2,2-Difluoro-1,3-diketones with Chiral Frustrated Lewis Pairs

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Chinese Journal of Chemistry 2024年第8期42卷 853-857页

作者： Ting Liu Xiangqing feng Haifeng du Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190 China University of Chinese Academy of Sciences Beijing100049 China

Comprehensive Summary,The asymmetric partial reduction of 1,3-diketones stands as a straightforward pathway to access optically active β-hydroxyketones. In this paper, an asymmetric Piers-type hydrosilylation of 2,2-difluoro-1,3-diketones was successfully realized by using a frustrated Lewis pair of chiral borane and tricyclohexylphosphine as a catalyst, delivering a variety of α,α-difluoro-β-hydroxyketones in high yields with up to 99% ee. Significantly, no over-reduced diol products were observed even with an excess amount of silanes. The product can be conveniently converted to α,α-difluoro-β-hydroxyester or 1,3-anti-diol via an oxidation with m-CPBA or a reduction with DIBAL-H without obvious loss of ee.

关键词： Asymmetric catalysis Hydrosilylation Ketones Frustrated Lewis pairs Chiral boranes

Asymmetric Hydrogenation of Phenanthridines with Chiral Boranes

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Chinese Journal of Chemistry 2024年第6期42卷 631-635页

作者： Guangyu Cui Xiangqing feng Haifeng du Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190 China University of Chinese Academy of Sciences Beijing100049 China

The asymmetric hydrogenation of N-heteroarenes provides an efficient method for the synthesis of optically active cyclic secondary *** this paper,we described an asymmetric hydrogenation of phenanthridines using a chiral mono-alkene-derived borane.A variety of dihydrophenanthridines were furnished in high yields with up to 93%*** current catalytic system was very sensitive for the steric hindrance of *** substituents at one phenyl group of phenanthridines were required to obtain the high *** large substituents on the carbon of the C=N bonds would diminish the reactivity sharply.

关键词： Asymmetric catalysis Hydrogenation Nitrogen heterocycles Phenanthridines Frustrated Lewis pairs Chiral boranes

Multiscale observation in wide-spatial radar surveillance based on coherent FDA design

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Science China(Information Sciences) 2024年第2期67卷 232-252页

作者： Lei YU feng HE yi SU College of Electronics Science National University of Defense Technology

Wide-spatial radar surveillance missions are challenging tasks, requiring an increased power budget and agility in transmission aimed at extracting information from multiple targets in different environments. These requirements necessitate high transmitting degrees of freedom(DOF) to achieve the objective of multiscale observation for specific tasks in specialized regions of interest. Herein, we exploit the multiscale observation ability in wide-spatial radar surveillance based on frequency diverse array(FDA)radar. The proposed method facilitates spatial anisotropic control of multiple radar resources, including the transmitting waveforms, beampattern, and bandwidth. By utilizing a coherent FDA radar, we offer principles for the selection of baseband waveforms, in addition to the quantitative design of the beampattern gain and optimal bandwidth from the perspective of detection. The feasibility of the proposed method is validated through numerical experiments, thus indicating the potential in wide-spatial radar surveillance. Moreover,this work can be regarded as a preliminary attempt to gauge the efficacy of the computational array, a novel academic concept.

关键词： multi-scale observation wide-spatial surveillance frequency diverse array (FDA) beampattern synthesis frequency diversity gain computational array